In the field of medicine, it is often the case that liquid pharmaceuticals must be prepared for delivery to a patient by a syringe. Such preparation typically involves the withdrawing into a syringe of a diluent liquid contained in a first vial, the subsequent injection of that liquid from the syringe into a second vial which contains a blendable, dissolvable medicine in powder form, and thereafter the withdrawal of the now-blended pharmaceutical medicine from that second vial back into the syringe. It is most frequently, though not always, the situation that the first vial from which diluent liquid is withdrawn is smaller (in mouth-opening-diameter size) than the second vial wherein blending occurs--which second vial has a larger mouth-opening-diameter size. A procedure falling within this category is referred to herein as involving first a smaller-size vial, and thereafter a larger-size vial. One should note that such references to smaller, and larger vial sizes are related to mouth-opening sizes, and not necessarily to vial volume sizes. In the balance of preparation situations, two vials of the same mouth-opening size are employed throughout the operation.
To aid in the practice of such back-and-forth transfer/delivery of liquid between a vial and a syringe, and to take into account safety and health concerns regarding, inter alia, contaminization, loss of sterilization, and exposure of medical personnel to injuries from sharps (such as hypodermic needles), prior work in this field has witnessed the creation and development of various liquid-transfer devices, or interfaces, which allow both for convenient coupling to a syringe and to a vial for liquid transfer, and for minimization of the several kinds of safety and health concerns just mentioned.
Two issues which are not well addressed by known prior art approaches to such liquid-transfer requirements are, first, that highly convenient accommodation of transfer apparatus to the handling of two different vial sizes has not been offered, and second, that a testy problem, referred to as "foaming", has not apparently been well addressed. Foaming is a bubbling action which can and does readily occur during that part of a liquid-transfer process wherein diluent is injected into a vial containing dissolvable powdered medicine. Foaming introduces problematic air bubbles which must be removed before any delivery to a patient.
An important object of the present invention, accordingly, is to provide an improved form of liquid-transfer apparatus which offers all of the key advantages of known prior art devices aimed at this purpose, but which, in addition, avoids the drawbacks (i.e., the not well-addressed issues) mentioned above.
More specifically, an object of this invention is to provide such apparatus which readily and easily accommodates transfers back and forth of liquid between a syringe and vials of the same size, as well as such transfers between a syringe and vials of two different sizes.
Another significant object of the invention is to provide transfer apparatus which uniquely creates an "ejection" liquid-flow into a vial that contains dissolvable powdered medicine in a fashion that greatly minimizes, and in very many instances completely avoids, the problem mentioned above known as foaming.
Still a further object of the present invention is to provide liquid-transfer apparatus of the type generally outlined which includes a ported spike which pierces and extends through the usual elastomeric stopper found in a vial, and which, further, is constructed in such a manner that with the spike piercing a conventional stopper, ports in the spike are contained within the usually present inwardly facing "cup" in the stopper, and in particular, in a condition closely adjacent the base in the cup. This offering of the invention plays not only a role in achieving the immediately preceding stated object of the invention, but in addition, ensures a situation wherein it is possible, predictably, and with no special effort required, and during withdrawing of liquid from a vial, to gather substantially all of the liquid in that vial.
Considering what we view to be the preferred organization of the present invention, that organization takes fundamentally two different forms. In one form, which form is designed to deal with the situation where only vials of the same size are ever used, the apparatus of the invention employs but a single unit, which we refer to as a liquid-transfer device. This device has a syringe-coupling end, a vial-coupling end which is sized to accommodate coupling to the particular single vial size that will be encountered, and special liquid passage structure which extends effectively for communication between the two mentioned ends of the device. The second organizational form of the invention is aimed at addressing, inter alia, the situation where two different sizes of vials need to be coupled-to during a preparation operation. In this form of the invention, two components are employed. One of these is a liquid-transfer device of the kind just mentioned above, with this transfer device being sized, at its vial-coupling end, to accommodate coupling to the larger size of the two vials which will be addressed. The other component takes the form of a slider/adaptor that fits in a connected (such as nested), removable relationship with respect to the vial-coupling end in the transfer device to accommodate direct coupling to a vial of the smaller of the two vial sizes which will be addressed.
With respect to both of these two forms of the invention, when an appropriate vial (of any size) is coupled-to for a liquid-transfer operation, and under circumstances where liquid is being injected through the transfer device into an attached vial, the liquid passage structure mentioned above directs liquid flow into the vial via a pair of tiny, laterally facing ports which reside, relatively positionally, within the hollow interior of an annular projection formed in the vial's stopper, which hollow interior faces the interior of the vial. This conventional annular projection and hollow interior thereof define what is referred to herein as a cup that faces (axially) the interior of the associated vial, and the port in the apparatus of the invention is located within the interior of this cup and closely adjacent the base of the cup. With this relationship extant--a relationship which exists because of certain special constructional features proposed according to the invention--and with the two ports organized as generally described, liquid flow into a vial is predominantly generally radial in nature, and uniquely suited to creating major liquid flow into the vial down the inside wall of the vial to minimize foaming.
Another feature of this kind of relationship which exists between the ports of the invention and the stopper's cup under circumstances where liquid is being withdrawn from a vial is that, with appropriate inversion of a vial, substantially all of liquid content can easily be withdrawn.
These and other objects, features and advantages which are offered by the present invention will become more fully apparent as the description that now follows is read in conjunction with the accompanying drawings.